In a hollow-body guitar, such as an acoustical guitar having a sound hole formed in the top wall (i.e., sounding board) of the hollow body, the elongate neck of the guitar connects to the front or head end of the hollow body by a headblock arrangement which is fixed to the front end wall of the hollow body. This headblock arrangement normally includes an enlarged headblock disposed interiorly of the hollow body but fixed to the front end wall substantially at the center thereof, and the inner end of the neck is fixedly secured to the headblock, typically by means of an interfitting dovetail groove arrangement, bolts or glue. The tensioned strings extend along the upper face of the elongate neck and are secured adjacent the remote free end thereof, with the other ends of the strings being secured to the hollow body. Due to the tension in the strings and the raised position thereof relative to the connection of the neck to the headblock, a significant force moment is imposed on the connection between the neck and the headblock, and it has been observed that this force moment over time causes undesired distortion of the guitar.
Due to the necessity of providing a compliant soundboard and body, acoustic guitars are necessarily built of relatively thin planar elements, with internal and external reinforcing structure added only where necessary. This construction often requires several parts of the guitar to work together to provide sufficient structural integrity. The headblock alone typically forms only part of the structure necessary to reinforce the guitar body against the force moment of the neck; typically there is also a substantial length of fingerboard glued to the external surface of the soundboard, as well as internal reinforcing bracing glued to the soundboard under it. Despite this construction, the headblock in many guitars rotates over time as a result of the force moment of the neck, causing difficultly in playing.
At the neck end, the vibrating portion of the string rests on a support called the nut, and at the body end, the vibrating portion of the string, where the strings transmit vibration to the soundboard, rests on a support called a saddle which is mounted in a bridge. For a given string length, the distance from the nut and bridge to any specific fret is constant to within an extremely small variable. Thus, the fret at which the neck is joined to the body effectively locates the bridge on the soundboard, and an increased extension of neck outside the body, giving access to additional frets, locates the bridge closer to the neck joint area and soundhole. Since the proximity of the bridge to the other elements of the guitar has an effect on the tone of the instrument, there is an optimum range within which the bridge must be located. This range determines the fret at which the neck and body can be joined.
The soundhole of most, but not all, flattop guitars is bisected by the longitudinal central axis defined by the strings. The distance of the soundhole to the bridge affects the tonal response of the guitar, and it can be only partially covered by the fingerboard, if at all. Additionally, any internal structure on the inside surface of the soundboard to support the neck joint or fingerboard must not protrude under the open area of the soundhole for aesthetic as well as structural reasons.
Players desire access to as much of the playing surface of the fingerboard as possible. In order to maintain an acoustically appropriate bridge location, while still providing extended fingerboard access, a portion of the body of the guitar adjacent to the fingerboard is sometimes removed from the design of the instrument. This area, called the "cutaway", is necessarily in close proximity to the neck joint, and its design is constrained by the substantial structural requirement of this area.
There are designs in which the body of the guitar is formed by hollowing out a solid plank of wood and adding a top or back to form an internal cavity. While such guitar bodies can be formed to provide excellent access to upper portions of the fingerboard, they are necessarily of relatively heavy construction, due to the weak nature of end grain wood when reduced to a thin cross section. As such, these instruments are primarily suitable for electronic amplification, and the "acoustic" response function acts as a tonal modifier of the primary amplified sound. Obsolete designs and primitive folk instruments of similar "hollowed out" construction also exist, but they suffer from the aforementioned structural and/or tonal deficiencies, and are therefore not effective in producing reliable and responsive acoustic guitars by modern standards.
In previous attempts to provide access to upper portions of the fingerboard, constructions have been used that combine an internal headblock, to which the neck is fastened, with a relatively thin outer sidewall, typically approximately similar in thickness to the soundboard and back, which outer wall defines the external shape of the body of the instrument. A similar alternative method of construction utilizes a portion of the neck itself that extends into the body as the structural equivalent of a headblock.
In such constructions the headblock, or the portion of the neck extending inside the body, is a separate piece from the outer wall, and is adhesively fastened to only part of the inside of the outer wall or walls that define the neck end of the guitar body. Thus any structural rigidity which may be gained by the physical configuration of the relatively thin outer wall is compromised to some degree by it's flexibility. This flexibility requires the presence of other mechanical factors, such as an internal reinforcement structure, and possibly also a length of fingerboard bearing on the external surface of the soundboard to withstand the leverage of the neck.
Because of these requirements, most acoustic guitar designs that attempt to provide extended fingerboard access are not able to provide unimpeded access to the back of the neck in the extended access area, but provide only lateral access, retaining to some degree a supportive structure under the fingerboard in the extended access area.
There are pre-existing acoustic guitar designs in which the neck joins the body in the approximate center of an inwardly curved structure, so called "lyre guitars". These are highly stylized instruments in which hollow chambers extend parallel to the neck, on either side of it; in most cases there are connections between these long chambers and the peghead (the attachment point of the strings at the outer end of the neck). These long chambers are primarily ornamental and to a lesser degree acoustical in function, but they are not designed to stabilize the neck joint area of themselves, being constructed with relatively thin sidewalls. As such there is a separate headblock, or internal neck extension, in conjunction with internal bracing and a cross connection between the long side chambers and the peghead to help provide the required structural support for the neck. Because of the required internal construction to reinforce the neck joint area, the soundhole, or soundholes must be located to accommodate this construction.
Another problem experienced with hollow-body guitars, which problem is wholly nonrelated to the headblock problem discussed above, relates to the construction of the tailblock assembly so as to facilitate access to the interior of the hollow body, such as for maintenance or for mounting and accessing electronics. One attempt to facilitate access to the interior of the hollow body through the tailblock assembly involves the provision of a hollow ring-shaped tailblock having a removable access door or cover, as disclosed in my earlier U.S. Pat. No. 4,351,217. While the tailblock assembly of my '217 patent does provide desirable access to the interior of the hollow body while at the same time retaining the desirable strength and acoustic properties of the hollow body, nevertheless this earlier tailblock arrangement still possess disadvantages, particularly with respect to manufacturing complexities and costs. In this known tailblock assembly, the ringlike tailblock member is of a laminated construction and has an arcuate configuration or curvature corresponding to that of the rear end wall of the hollow body, and this makes manufacture of the tailblock member and assembly thereof to the guitar more costly and complex than desired. Also, this arrangement requires that the access door be recessed within the tailblock in order to recess electronic components.
Accordingly, it is an object of this invention to provide improved headblock and tailblock arrangements for a hollow-body guitar, which arrangements overcome the disadvantages associated with prior arrangements of this general type, as briefly discussed above.
More specifically, it is an object of this invention to provide an improved headblock arrangement having increased capability of withstanding the force moment created by the strings of the instrument, without detracting from either the acoustical properties of the hollow body or the overall appearance of the guitar.
A further object is to provide an improved headblock arrangement, as aforesaid, which provides the user with increased access to the strings located more closely adjacent the hollow body.
It is also an object of the invention to provide an improved tailblock arrangement which provides access to the interior of the hollow body for maintenance or for mounting electronics, but which arrangement can be economically manufactured and assembled to the hollow body, which permit the exterior electronic components to be desirably recessed, and which does not detract from the overall appearance of the guitar.
Still a further object of the invention is to provide an improved hollow-body guitar wherein incorporation of both the improved headblock arrangement and the improved tailblock arrangement provides the overall guitar with not only improved structural characteristics but also provides the guitar with a desirable appearance.
The stringed musical instrument of this invention includes a hollow body having top and bottom walls joined by a peripheral rim or sidewall, the top wall preferably having a hole therethrough and functioning as a sounding board. An elongate neck member is fixed to and projects outwardly from the guitar in the longitudinal direction thereof, and a plurality of tensioned strings extend along the upper surface of the neck member, with one end of the strings being anchored adjacent the free or head end of the neck member. The other end of the strings are anchored to the hollow body. The rear or tail end of the neck member is fixedly anchored to the front or head end of the hollow body by a headblock arrangement. In the guitar of this invention, the head end of the hollow body is formed with a front end wall having a concave arcuate configuration which defines a large concave recess which opens outwardly in the forward direction. This recess is substantially bisected by the neck member as it projects longitudinally outwardly from the hollow body. The headblock arrangement includes a headblock which effectively defines the front end wall of the hollow body and is of a concave arcuate configuration, with the tail end of the neck member being fixed to this headblock substantially at a center portion thereof. The arcuate configuration of the headblock defines side or wing portions which project sidewardly and forwardly from the center portion so as to terminate in free ends or tip parts which are spaced longitudinally forwardly a substantial distance from the center portion. This creates a significant torsional or moment strength in the longitudinal direction of the guitar to resist the longitudinal force moment created by the strings. The concave recess defined at the head end of the guitar also provides increased access space for the user's hands to facilitate access to the strings at a location closer to the sound hole, that is, to facilitate access to the higher frets.
The stringed musical instrument of the invention also comprises a hollow-body guitar having the general construction briefly described above, preferably including the improved headblock arrangement briefly described above, and also incorporating a slotlike recess or opening which is formed in the rear or tail end of the hollow body and projects longitudinally inwardly a small extent. This recess is formed through the top and bottom walls, and the sides of the recess are formed by opposed wall parts defined on a U-shaped tailblock which defines at least part of the rear end wall of the hollow body. The tailblock includes a hollow ringlike block part which is of a generally flat configuration and is mounted in longitudinally forwardly spaced relation from the remote or rearward end of the hollow body. This ringlike block part, on the rear race thereof, mounts a removable door or access panel to facilitate access to the interior of the hollow body, either for purposes of maintenance or for permitting mounting of or access to an electronic pick-up and associated electronics and controls.
In the instrument of this invention, the sidewall which defines the neck end of the guitar is constructed of laminated wooden veneer or of a synthetic material. It is inwardly curved, and the neck attaches directly to it. It is of sufficient strength so that it alone provides all, or virtually all of the structural rigidity necessary. Internal structure is kept to a minimum, and because of the rigid nature of the end wall itself, it's reliance on any internal reinforcement disposed towards the bridge is minimal or nonexistent. This minimal internal construction allows the neck to join the body closer to the soundhole and bridge without requiring any adaptation of their location relative to the rest of the guitar body. This construction also does not depend on any downbearing pressure of the fingerboard to stabilize the neck against rotation. This allows the portion of the fingerboard over the body to be extremely short, and frees it of any required adhesive or mechanical fastening to the soundboard. The neck may be removable from the body by simply unbolting it from the curved headblock. Additionally, because no supportive structure is required under the extended access area of the neck, there is full access to the back of the neck in this area.
Other objects and purposes of the invention will be apparent to persons familiar with instruments of this general type upon reading the following specification and inspecting the accompanying drawings.